Analog Module

S7200 Programmable Controller System Manual

400

Analog Expansion Modules Specifications

Table A15 Analog Expansion Modules Order Numbers

Order Number Expansion Model EM Inputs EM Outputs RemovableConnector

6ES7 2310HC220XA0 EM 231 Analog Input, 4 Inputs 4 No

6ES7 2320HB220XA0 EM 232 Analog Output, 2 Outputs 2 No

6ES7 2350KD220XA0 EM 235 Analog Combination 4 Inputs/1 Output 4 11 No

1 The CPU reserves 2 analog output points for this module.

Table A16 Analog Expansion Modules General Specifications

Order Number Module Name andDescription

Dimensions (mm)(W x H x D)

Weight Dissipation VDC Requirements+5 VDC +24 VDC

6ES7 2310HC220XA0 EM 231 Analog Input,4 Inputs

71.2 x 80 x 62 183 g 2 W 20 mA 60 mA

6ES7 2320HB220XA0 EM 232 Analog Output,2 Outputs

46 x 80 x 62 148 g 2 W 20 mA 70 mA (with bothoutputs at 20 mA)

6ES7 2350KD220XA0 EM 235 Analog Combination4 Inputs/1 Output

71.2 x 80 x 62 186 g 2 W 30 mA 60 mA (with outputat 20 mA)

Table A17 Analog Expansion Modules Input Specifications

General 6ES7 2310HC220XA0 6ES7 2350KD220XA0

Data word formatBipolar, fullscale rangeUnipolar, fullscale range

(See Figure A14)32000 to +320000 to 32000

(See Figure A14)32000 to +320000 to 32000

DC Input impedance 10 M voltage input250 current input

10 M voltage input250 current input

Input filter attenuation 3 db at 3.1 Khz 3 db at 3.1 KhzMaximum input voltage 30 VDC 30 VDCMaximum input current 32 mA 32 mAResolution

BipolarUnipolar

11 bits plus 1 sign bit12 bits

Isolation (field to logic) None NoneInput type Differential DifferentialInput ranges

VoltageCurrent

Selectable, see Table A20 for available ranges0 to 20 mA

Selectable, see Table A21 for available ranges0 to 20 mA

Input resolution See Table A20 See Table A21Analog to digital conversion time < 250 s < 250 sAnalog input step response 1.5 ms to 95% 1.5 ms to 95%Common mode rejection 40 dB, DC to 60 Hz 40 dB, DC to 60 HzCommon mode voltage Signal voltage plus common mode voltage

must be 12 VSignal voltage plus common mode voltagemust be 12 V

24 VDC supply voltage range 20.4 to 28.8 VDC (Class 2, Limited Power, or sensor power from PLC)

Technical Specifications Appendix A

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Table A18 Analog Expansion Modules Output Specifications

General 6ES7 2320HB220XA0 6ES7 2350KD220XA0

Isolation (field to logic) None NoneSignal range

Voltage outputCurrent output

10 V0 to 20 mA

10 V0 to 20 mA

Resolution, fullscaleVoltageCurrent

12 bits plus sign bit11 bits

11 bits plus sign bit11 bits

Data word formatVoltageCurrent

32000 to +320000 to +32000

32000 to +320000 to +32000

AccuracyWorst case, 0p to 55p C

Voltage outputCurrent output

Typical, 25p CVoltage outputCurrent output

2% of fullscale2% of fullscale

0.5% of fullscale0.5% of fullscale

2% of fullscale2% of fullscale

0.5% of fullscale0.5% of fullscale

Setting timeVoltage outputCurrent output

100 S2 mS

100 S2 mS

Maximum driveVoltage outputCurrent output

5000 minimum500 maximum

5000 minimum500 maximum

24 VDC supply voltage range 20.4 to 28.8 VDC (Class 2, Limited Power, or sensor power from PLC)


402

M

420mA

020mA

EM 231 Analog Input,4 Inputs(6ES7 2310HC220XA0)

EM 232 Analog Output,2 Outputs(6ES7 2320HB220XA0)

EM 235 Analog Combination4 Inputs/1 Output(6ES7 2350KD220XA0)

RA A+ A RB B+ B RC C+ C RD D+ D

M L+

+

+

Gain Configuration

M0 V0 I0 M1 V1 I1

M L+

24VDCPower

24VDCPower

+

24VDCPower

L+

D

M

RA A+ A RB B+ B RC C+ C RD D+

+

Gain ConfigurationM0 Offset

+

V0 I0

250 Ohms (builtin) 250 Ohms (builtin)

PS PS

+

L+ M

020mA

PS PS

+

420mA

L+ M

+

M

Current

UnusedVoltage

Current

UnusedVoltage

Figure A12 Wiring Diagrams for Analog Expansion Modules


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Analog LED IndicatorsThe LED indicators for the analog modules are shown in Table A19.

Table A19 Analog LED IndicatorsLED Indicator ON OFF

24 VDC Power Supply Good No faults No 24 VDC power

TipThe state of user power is also reported in Special Memory (SM) bits. For more information, seeAppendix D, SMB8 to SMB21 I/O Module ID and Error Registers.

Input CalibrationThe calibration adjustments affect the instrumentation amplifier stage that follows the analogmultiplexer (see the Input Block Diagram for the EM 231 in Figure A15 and EM 235 in FigureA16). Therefore, calibration affects all user input channels. Even after calibration, variations in thecomponent values of each input circuit preceding the analog multiplexer will cause slightdifferences in the readings between channels connected to the same input signal.

To meet the specifications, you should enable analog input filters for all inputs of the module.Select 64 or more samples to calculate the average value.

To calibrate the input, use the following steps.

1. Turn off the power to the module. Select the desired input range.

2. Turn on the power to the CPU and module. Allow the module to stabilize for 15 minutes.

3. Using a transmitter, a voltage source, or a current source, apply a zero value signal to oneof the input terminals.

4. Read the value reported to the CPU by the appropriate input channel.

5. Adjust the OFFSET potentiometer until the reading is zero, or the desired digital data value.

6. Connect a fullscale value signal to one of the input terminals. Read the value reported tothe CPU.

7. Adjust the GAIN potentiometer until the reading is 32000, or the desired digital data value.

8. Repeat OFFSET and GAIN calibration as required.

Calibration and Configuration Location for EM 231 and EM 235Figure A13 shows the calibration potentiometer and configuration DIP switches located on theright of the bottom terminal block of the module.


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Fixed Terminal Block Gain Configuration Offset

OnOff

OnOff

Fixed Terminal Block Gain Configuration

EM 231 EM 235

Figure A13 Calibration Potentiometer and Configuration DIP Switch Location for the EM 231 and EM 235

Configuration for EM 231Table A20 shows how to configure the EM 231 module using the configuration DIP switches.Switches 1, 2, and 3 select the analog input range. All inputs are set to the same analog inputrange. In this table, ON is closed, and OFF is open. The switch settings are read only when thepower is turned on.

Table A20 EM 231 Configuration Switch Table to Select Analog Input RangeUnipolar

Full Scale Input ResolutionSW1 SW2 SW3

FullScale Input Resolution

OFF ON 0 to 10 V 2.5 mVON

ON OFF0 to 5 V 1.25 mVON

ON OFF 0 to 20 mA 5 ABipolar

Full Scale Input ResolutionSW1 SW2 SW3


OFFOFF ON 5 V 2.5 mV

OFFON OFF 2.5 V 1.25 mV


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Configuration for EM 235Table A21 shows how to configure the EM 235 module using the configuration DIP switches.Switches 1 through 6 select the analog input range and resolution. All inputs are set to the sameanalog input range and format. Table A21 shows how to select for unipolar/bipolar (switch 6), gain(switches 4 and 5), and attenuation (switches 1, 2, and 3). In these tables, ON is closed, and OFFis open. The switch settings are read only when the power is turned on.

Table A21 EM 235 Configuration Switch Table to Select Analog Range and ResolutionUnipolar

Full Scale Input ResolutionSW1 SW2 SW3 SW4 SW5 SW6


ON OFF OFF ON OFF ON 0 to 50 mV 12.5 "VOFF ON OFF ON OFF ON 0 to 100 mV 25 "VON OFF OFF OFF ON ON 0 to 500 mV 125 "VOFF ON OFF OFF ON ON 0 to 1 V 250 "VON OFF OFF OFF OFF ON 0 to 5 V 1.25 mVON OFF OFF OFF OFF ON 0 to 20 mA 5 "AOFF ON OFF OFF OFF ON 0 to 10 V 2.5 mV

BipolarFull Scale Input Resolution

SW1 SW2 SW3 SW4 SW5 SW6FullScale Input Resolution

ON OFF OFF ON OFF OFF +25 mV 12.5 "VOFF ON OFF ON OFF OFF +50 mV 25 "VOFF OFF ON ON OFF OFF +100 mV 50 "VON OFF OFF OFF ON OFF +250 mV 125 "VOFF ON OFF OFF ON OFF +500 mV 250 "VOFF OFF ON OFF ON OFF +1 V 500 "VON OFF OFF OFF OFF OFF +2.5 V 1.25 mVOFF ON OFF OFF OFF OFF +5 V 2.5 mVOFF OFF ON OFF OFF OFF +10 V 5 mV


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Input Data Word Format for EM 231 and EM 235Figure A14 shows where the 12bit data value is placed within the analog input word of the CPU.

15 3MSB LSB

0AIW XX0

0 0 0214

Data value 12 Bits

Unipolar data

15 3MSB LSB

AIW XX0

0 0 0Data value 12 Bits

Bipolar data

40

Figure A14 Input Data Word Format for EM 231 and EM 235

TipThe 12 bits of the analogtodigital converter (ADC) readings are leftjustified in the data wordformat. The MSB is the sign bit: zero indicates a positive data word value.In the unipolar format, the three trailing zeros cause the data word to change by a count of eightfor each onecount change in the ADC value.In the bipolar format, the four trailing zeros cause the data word to change by a count of sixteenfor each one count change in the ADC value.

Input Block Diagram for EM 231 and EM 235

CC

A+

RA

A

Rloop

C

CC

B+

RB

B

Rloop

C

CC

C+

RC

C

Rloop

A=1

A=2

A=3

Input filter MUX 4 to 1

BUFFER

011

A/D Converter

A=4

C

CC

D+

RD

D

Rloop

GAIN ADJUST

InstrumentationAMP

+

EM 231CR

R

R

R

R

R

R

R

Figure A15 Input Block Diagram for the EM 231


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REF_VOLT

C

CC

A+

RA

A

Rloop

C

CC

B+

RB

B

Rloop

C

CC

C+

RC

C

Rloop

A=1

A=2

A=3

Buffer+

Input filter MUX 4 to 1

BUFFER

DATA011

A/D Converter

EM 235

A=4

C

CC

D+

RD

D

Rloop

GAIN ADJUST

InstrumentationAMP

+

Offset Adjust

R

R

R

R

R

R

R

R

Figure A16 Input Block Diagram for the EM 235

Output Data Word Format for EM 232 and EM 235Figure A17 shows where the 12bit data value is placed within the analog output word of theCPU.

15 4MSB LSB

0AQW XX0

0 0 0314

Data value 11 BitsCurrent output data format

15 3MSB LSB

AQW XX0

0 0 0Data value 12 BitsVoltage output data format

40

0

Figure A17 Output Data Word Format for EM 232 and EM 235

TipThe 12 bits of the digitaltoanalog converter (DAC) readings are leftjustified in the output dataword format. The MSB is the sign bit: zero indicates a positive data word value. The four trailingzeros are truncated before being loaded into the DAC registers. These bits have no effect on theoutput signal value.


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Output Block Diagram for EM 232 and EM 235

DATA 11 0

VrefD/A converter

Digitaltoanalog converter

+

R

R

Vout10.. +10 Volts

M

Voltage output buffer

+/ 2V

+

+

R

Iout0..20 mA

100

+24 Volt

Voltagetocurrent converter

1/4

R

Figure A18 Output Block Diagram for the EM 232 and EM 235

Installation GuidelinesUse the following guidelines to ensure accuracy and repeatability:

! Ensure that the 24VDC Sensor Supply is free of noise and is stable.

! Use the shortest possible sensor wires.

! Use shielded twisted pair wiring for sensor wires.

! Terminate the shield at the Sensor location only.

! Short the inputs for any unused channels, as shown in Figure A18.

! Avoid bending the wires into sharp angles.

! Use wireways for wire routing.

! Avoid placing signal wires parallel to highenergy wires. If the two wires must meet, crossthem at right angles.

! Ensure that the input signals are within the common mode voltage specification by isolatingthe input signals or referencing them to the external 24V common of the analog module.

TipThe EM 231 and EM 235 expansion modules are not recommended for use withthermocouples.


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Understanding the Analog Input Module: Accuracy and RepeatabilityThe EM 231 and EM 235 analog input modules are lowcost, highspeed 12 bit analog inputmodules. The modules can convert an analog signal input to its corresponding digital value in149 sec. The analog signal input is converted each time your program accesses the analogpoint. These conversion times must be added to the basic execution time of the instruction usedto access the analog input.

The EM 231 and EM 235 provide an unprocesseddigital value (no linearization or filtering) thatcorresponds to the analog voltage or current presentedat the module’s input terminals. Since the modules arehighspeed modules, they can follow rapid changes inthe analog input signal (including internal and externalnoise).

You can minimize readingtoreading variations causedby noise for a constant or slowly changing analog inputsignal by averaging a number of readings. Note thatincreasing the number of readings used in computingthe average value results in a correspondingly slower

Repeatability limits(99% of all readings fall within these limits)

Average Value

Mean(average)Accuracy

Signal Input

the average value results in a correspondingly slowerresponse time to changes in the input signal. Figure A19 Accuracy Definitions

Figure A19 shows the 99% repeatability limits, the mean or average value of the individualreadings, and the mean accuracy in a graphical form.

The specifications for repeatability describe the readingtoreading variations of the module for aninput signal that is not changing. The repeatability specification defines the limits within which 99%of the readings will fall. The repeatability is described in this figure by the bell curve.

The mean accuracy specification describes the average value of the error (the difference betweenthe average value of individual readings and the exact value of the actual analog input signal).

Table A22 gives the repeatability specifications and the mean accuracy as they relate to each ofthe configurable ranges.


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Definitions of the Analog Specifications! Accuracy: deviation from the expected value on a given point

! Resolution: the effect of an LSB change reflected on the output.

Table A22 EM 231 and EM 235 Specifications

Full Scale Input Repeatability1 Mean (average) Accuracy1,2,3,4Full Scale InputRange % of Full Scale Counts % of Full Scale Counts

EM 231 Specifications

0 to 5 V0 to 20 mA 24 0.1%

0 to 10 V 0.075%24 0.1%

322.5 V

0.075%

48 0 05%

32

5 V 48 0.05%

EM 235 Specifications

0 to 50 mV 0.25% 800 to 100 mV 0.2% 640 to 500 mV

0 to 1 V 0.075% 240 to 5 V

0 0 5%0.05% 16

0 to 20 mA0 05% 6

0 to 10 V25 mV 0.25% 16050 mV 0.2% 128

100 mV 0.1% 64250 mV500 mV 0.075% 48

1 V0.075% 48

0 05% 322.5 V 0.05% 32

5 V10 V

1 Measurements made after the selected input range has been calibrated.2 The offset error in the signal near zero analog input is not corrected, and is not included in the accuracy specifications.3 There is a channeltochannel carryover conversion error, due to the finite settling time of the analog multiplexer. The maximum carryover

error is 0.1% of the difference between channels.4 Mean accuracy includes effects of nonlinearity and drift from 0 to 55 degrees C.


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Thermocouple and RTD Expansion Modules Specifications

Table A23 Thermocouple and RTD Modules Order Numbers

Order Number Expansion Model EM Inputs EM Outputs RemovableConnector

6ES7 2317PD220XA0 EM 231 Analog Input Thermocouple, 4 Inputs 4 Thermocouple No

6ES7 2317PB220XA0 EM 231 Analog Input RTD, 2 Inputs 2 RTD No

Table A24 Thermocouple and RTD Modules General Specifications

Order Number Module Name and Description Dimensions (mm)(W x H x D)

Weight Dissipation VDC Requirements+5 VDC +24 VDC

6ES7 2317PD220XA0 EM 231 Analog Input Thermocouple,4 Inputs

71.2 x 80 x 62 210 g 1.8 W 87mA 60 mA

6ES7 2317PB220XA0 EM 231 Analog Input RTD, 2 Inputs 71.2 x 80 x 62 210 g 1.8 W 87 mA 60 mA

Table A25 Thermocouple and RTD Modules Specifications

General 6ES7 2317PD220XA0Thermocouple

6ES7 2317PB220XA0RTD

IsolationField to logicField to 24 VDC24 VDC to logic

500 VAC500 VAC500 VAC

500 VAC500 VAC500 VAC

Common mode input range(input channel to input channel)

120 VAC 0

Common mode rejection > 120 dB at 120 VAC > 120 dB at 120 VACInput type Floating TC Module ground referenced RTDInput ranges1 TC types (select one per module)

S, T, R, E, N, K, JVoltage range : +/ 80 mV

RTD types (select one per module):platinum (Pt), copper (Cu), nickel (Ni), orResistanceSee Table A30 for available RTD types.

Input resolutionTemperatureVoltageResistance

0.1p C / 0.1p F15 bits plus sign

0.1p C / 0.1p F15 bits plus sign

Measuring Principle Sigmadelta SigmadeltaModule update time: All channels 405 ms 405 ms (700 ms for Pt10000)Wire length 100 meters to sensor max. 100 meters to sensor maxò

Wire loop resistance 100 max. 20 , 2.7 for Cu max.Suppression of interference 85 dB at 50 Hz/60 Hz/ 400 Hz 85 dB at 50 Hz/60 Hz/400 HzData word format Voltage: 27648 to + 27648 Resistance: 0 to +27648Maximum sensor dissipation 1m WInput impedance 1 M 10 MMaximum input voltage 30 VDC 30 VDC (sense), 5 VDC (source)Input filter attenuation 3 db at 21 kHz 3 db at 3.6 kHzBasic error 0.1% FS (voltage) 0.1% FS (resistance)Repeatability 0.05% FS 0.05% FSCold junction error 1.5 p C 24 VDC supply voltage range 20.4 to 28.8 VDC 20.4 to 28.8 VDC

1 The input range selection (temperature, voltage on resistance) applies to all channels on the module.


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EM 231AI 2 x RTD

EM 231 Analog Input RTD, 2 Inputs(6ES7 2317PB220XA0)

A+ A B+ B C+ C D+

24 VDCpower

DEM 231AI 4

EM 231 Analog Input Thermocouple, 4 Inputs(6ES7 2317PD220XA0)

+ + + +

A+ A a+ a B+ B b+ b

M L+M L+

+

24 VDCpower

Configuration Configuration

+

Figure A20 Connector Terminal Identification for EM 231 Thermocouple and EM 231 RTD Modules

CompatibilityThe RTD and Thermocouple modules are designed to work with the CPU 222, CPU 224,CPU 224XP and CPU 226.

TipThe RTD and Thermocouple modules are designed to give maximum performance wheninstalled in a stable temperature environment.The EM 231 Thermocouple module, for example, has special cold junction compensationcircuitry that measures the temperature at the module connectors and makes necessarychanges to the measurement to compensate for temperature differences between the referencetemperature and the temperature at the module. If the ambient temperature is changing rapidlyin the area where the EM 231 Thermocouple module is installed, additional errors areintroduced.To achieve maximum accuracy and repeatability, Siemens recommends that the S7200 RTDand Thermocouple modules be mounted in locations that have stable ambient temperature.

Noise ImmunityUse shielded wires for best noise immunity. If a thermocouple input channel is not used, short theunused channel inputs, or connect them in parallel to another channel.

Analog Module

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